Field of the Invention
The present embodiments relate to a sheet-conveying device disposed in an image-forming apparatus that forms an image on a sheet.
Description of the Related Art
In an image-forming apparatus, sheets are supplied to an image-forming unit one by one from a sheet tray onto which a stack of the sheets are loaded, the image-forming unit forms an image on each sheet on the basis of inputted image signals, and the sheet is subsequently discharged to the outside of the image-forming apparatus. Among such image-forming apparatuses, there is an image-forming apparatus that enables duplex image forming (duplex printing) in a manner in which, after an image is formed on one surface (first surface) of a sheet, the sheet is inverted by an inverting portion and conveyed again to the image-forming unit, and an image is formed on the opposite surface (second surface) of the sheet.
Some types of inverting portions of image-forming apparatuses that enable duplex image forming include reverse rollers that can rotate in a forward direction and a reverse direction and that temporarily discharges a sheet to the outside of the image-forming apparatuses and switch the rotation direction of the reverse rollers back and forth between the forward direction and the reverse direction so as to invert the sheet. When the sheet is inverted in such a switching-back-type inverting portion, part of the sheet is first discharged to a discharge tray with the reverse rollers holding the rear end of the sheet in a conveyance direction.
The rotation direction of the reverse rollers is subsequently switched to the direction opposite to a discharge direction such that the rear end in the conveyance direction becomes the leading end, and the sheet is thereby fed to a duplex conveyance path for printing of the second surface. After an image is formed on the second surface, the sheet is finally discharged to the discharge tray from a discharge portion by using discharge rollers. Thus, the image-forming apparatuses typically include the discharge portion that discharges the sheet and the inverting portion that inverts the sheet as separated components in order to improve productivity in printing, as disclosed in Japanese Patent Laid-Open No. 2004-302182.
In the case where a pair of the discharge rollers disposed downstream of a fixing device is located close to a pair of the reverse rollers for duplex printing, there are problems of a complicated conveyance path and a large size of the apparatus.